title: Emotional processing of personally familiar faces in the vegetative state.
abstract: BACKGROUND
  The Vegetative State (VS) is a severe disorder of consciousness in which patients are awake but display no signs of awareness. Yet, recent functional magnetic resonance imaging (fMRI) studies have demonstrated evidence for covert awareness in VS patients by recording specific brain activations during a cognitive task. However, the possible existence of incommunicable subjective emotional experiences in VS patients remains largely unexplored. This study aimed to probe the question of whether VS patients retain a brain ability to selectively process external stimuli according to their emotional value and look for evidence of covert emotional awareness in patients.
  
  
  RESULTS
  In order to explore these questions we employed the emotive impact of observing personally familiar faces, known to provoke specific perceptual as well as emotional brain activations. Four VS patients and thirteen healthy controls first underwent an fMRI scan while viewing pictures of non-familiar faces, personally familiar faces and pictures of themselves. In a subsequent imagery task participants were asked to actively imagine one of their parent's faces. Analyses focused on face and familiarity selective regional brain activations and inter-regional functional connectivity. Similar to controls, all patients displayed face selective brain responses with further limbic and cortical activations elicited by familiar faces. In patients as well as controls, Connectivity was observed between emotional, visual and face specific areas, suggesting aware emotional perception. This connectivity was strongest in the two patients who later recovered. Notably, these two patients also displayed selective amygdala activation during familiar face imagery, with one further exhibiting face selective activations, indistinguishable from healthy controls.
  
  
  CONCLUSIONS
  Taken together, these results show that selective emotional processing can be elicited in VS patients both by external emotionally salient stimuli and by internal cognitive processes, suggesting the ability for covert emotional awareness of self and the environment in VS patients.
authors.affiliation: Functional Brain Center, Wohl Institute for Advanced Imaging, Sourasky Medical Center, Tel Aviv, Israel ; Department of Internal Medicine, Sourasky Medical Center, Tel Aviv, Israel ; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Haggai
authors.initials: H
authors.lastname: Sharon
authors.forename: Yotam
authors.initials: Y
authors.lastname: Pasternak
authors.forename: Eti
authors.initials: E
authors.lastname: Ben Simon
authors.forename: Michal
authors.initials: M
authors.lastname: Gruberger
authors.forename: Nir
authors.initials: N
authors.lastname: Giladi
authors.forename: Ben Zion
authors.initials: BZ
authors.lastname: Krimchanski
authors.forename: David
authors.initials: D
authors.lastname: Hassin
authors.forename: Talma
authors.initials: T
authors.lastname: Hendler
mesh_terms: D000328:Adult; D001364:Awareness / Q000502:physiology; D003710:Demography; D004644:Emotions / Q000502:physiology*; D005145:Face / Q000503:physiopathology; D005260:Female; D006801:Humans; D019018:Imagery, Psychotherapy; D008297:Male; D008875:Middle Aged; D010465:Perception / Q000502:physiology; D018458:Persistent Vegetative State / Q000503:physiopathology*; D021641:Recognition, Psychology